Project Summary/Abstract for Biomechanics Core While musculoskeletal tissues have multiple biological roles, their primary function is to provide mechanical load support and motion to the body to enable the activities of daily living. These load and deformation requirements vary with tissue type and location, but include significant mechanical complexity such as high stiffness and strength, anisotropy, nonlinearity, and viscoelasticity. With injury, aging, degeneration, or disease, musculoskeletal tissues may experience a decline in mechanical function, and this loss of function can originate at different length scales. With development, growth, and therapeutic treatment, the mechanical function can improve and change across these same length scales. In short, it is essential that assessment of musculoskeletal tissue mechanics be a primary focus in both basic and translational studies of musculoskeletal tissue formation, development, degeneration, and treatment. Moreover, the innovation and sophistication of biomechanical quantification must continue at a pace on par with the ever-deepening knowledge of musculoskeletal tissue molecular biology, with advances in molecular and imaging technologies, and with new therapeutic developments in order to discern the functional outcomes in these studies. In particular, biomechanical testing must provide information across length scales to inform our understanding of degeneration and regeneration processes. Therefore, the overall objective of the Biomechanics Core is to develop and provide a wide range of innovative biomechanical approaches to evaluate musculoskeletal tissue function in the context of damage, repair, and regeneration, and to provide training and funding for new projects and collaborations utilizing these assays. Over the last decade, our Biomechanics Core at the Penn Center for Musculoskeletal Disorders (PCMD) has grown into a thriving resource for the University of Pennsylvania and Philadelphia area musculoskeletal research community. In this submission, we will further expand our services to meet the increased demand for specialized techniques and develop new and innovative methods that address the multi-scale mechanics of musculoskeletal tissues. These developments will provide customized services that enhance the research productivity of our members. The Specific Aims of the Biomechanics Core are: 1) To provide guidance and training on the capabilities, advantages, and disadvantages of the various methodologies to assess musculoskeletal tissue biomechanical function through formal educational enrichment programs and one-on-one interactions, 2) To provide expertise and service for biomechanical assays of musculoskeletal tissues, 3) To develop innovative biomechanical testing techniques that will be applicable to musculoskeletal research, and in particular those that provide information across tissue length scales, and 4) To provide funding for the development of new projects and collaborations and to develop preliminary and/or feasibility data for investigators.